The first prototype coupled FDR/CVR [Flight Data Recorder/Cockpit Voice Recorder] designed with civilian aircraft in mind, for explicit post-crash examination purposes, was produced in 1956 by Dr. David Warren of the Defence Science and Technology Organisations', Aeronautical Research Laboratories in Melbourne, Australia. In 1953 and 1954, a series of fatal accidents involving the De Havilland DH106 Comet prompted the grounding of the entire fleet pending an investigation. Dr. Warren, a chemist specializing in aircraft fuels, was involved in a professional committee discussing the possible causes. Since there had been neither witnesses nor survivors, Dr. Warren conceived of a crash-survivable method to record the flight crew's conversation (and other pre-crash data), reasoning they would greatly assist in determining a cause and enabling the prevention of future, avoidable accidents of the same type.
Despite his 1954 report entitled "A Device for Assisting Investigation into Aircraft Accidents" and a 1957 prototype FDR called "The ARL Flight Memory Unit", aviation authorities from around the world were largely uninterested. This changed in 1958 when Sir Robert Hardingham, the Secretary of the UK Air Registration Board, visited the ARL and was introduced to Warren.In 1960, the judge in an enquiry into an aircraft crash in Mackay, Queensland, recommended the installation of flight recorders in all airliners. As a result, Australia became the first country to make cockpit voice recording compulsory.
Vale, Dr Warren, and thank you for your important contribution to air safety.